The California Department of Public Health is investigating the case of a child who contracted the plague at Yosemite National Park. No other members of the child’s family have reported symptoms. “Human cases of plague are rare, with the last reported human infection in California occurring in 2006,” Public Health Director and State Health Officer Karen Smith said in a statement. The disease is typically carried by squirrels, chipmunks, and other rodents, as well as fleas. Yosemite is providing visitors with information about how to prevent exposure while public health officials conduct an environmental evaluation.